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[Resumen] La caracterización de superficies es un problema abordado desde diferentes áreas de la ingeniería, como la mecánica, la óptica o la electrónica, entre otras. En este estudio, se presenta un método basado en el uso de un robot en modo control de fuerza para caracterizar de la firmeza de la superficie de un balón según su presión interna. Los parámetros de la respuesta subamortiguada el régimen transitorio cuando el robot está programado para encontrar un valor de fuerza permiten identificar la firmeza de la superficie de contacto que en este caso está relacionado con la presión interna del balón contra el que contacta. Los ensayos han sido realizados empleando siempre el mismo ajuste del sistema de control de fuerza del robot logrando para las distintas presiones analizadas una respuesta subamortiguada de segundo orden. Los resultados obtenidos demuestran las posibilidades y precisión del método propuesto para la caracterización de superficies de firmeza variable. Este enfoque tiene aplicaciones potenciales en la industria, como la evaluación de la firmeza de objetos a manipular o la de productos hortofrutícolas., [Abstract] Surface characterization is a problem in different engineering fields, such as mechanics, optics, and electronics. This study presents a method based on using a force-controlled robot to characterize the firmness of a surface, specifically a ball, based on its internal pressure. The parameters of the underdamped response in the transient response, when the robot is programmed to find a force value, allow for identifying the contact surface firmness, which is related to the internal pressure of the ball it contacts. The experiments were conducted using the same force control system setting for all different ball pressures, resulting in a second-order underdamped response. The obtained results demonstrate the possibilities and accuracy of the proposed method for characterizing surfaces with varying firmness. This approach has potential applications in various industries, such as evaluating the firmness of objects to be manipulated or horticultural products.

[EN] A tool for human pose estimation and quantification using consumer-level equipment is a long-pursued objective. Many studies have employed the Microsoft Kinect v2 depth camera but with recent release of the new Kinect Azure a revision is required. This work researches the specific case of estimating the range of motion in five upper limb exercises using four different pose estimation methods. These exercises were recorded with the Kinect Azure camera and assessed with the OptiTrack motion tracking system as baseline. The statistical analysis consisted of evaluation of intra-rater reliability with intra-class correlation, the Pearson correlation coefficient and Bland-Altman statistical procedure. The modified version of the OpenPose algorithm with the post-processing algorithm PoseFix had excellent reliability with most intra-class correlations being over 0.75. The Azure body tracking algorithm had intermediate results. The results obtained justify clinicians employing these methods, as quick and low-cost simple tools, to assess upper limb angles

[EN] Traditionally Caenorhabditis elegans lifespan assays are performed by manually inspecting nematodes with a dissection microscope, which involves daily counting of live/dead worms cultured in Petri plates for 21-25 days. This manual inspection requires the screening of hundreds of worms to ensure statistical robustness, and is therefore a time-consuming approach. In recent years, various automated artificial vision systems have been reported to increase the throughput, however they usually provide less accurate results than manual assays. The main problems identified when using these vision systems are the false positives and false negatives, which occur due to culture media changes, occluded zones, dirtiness or condensation of the Petri plates. In this work, we developed and described a new C. elegans monitoring machine, SiViS, which consists of a flexible and compact platform design to analyse C. elegans cultures using the standard Petri plates seeded with E. coli. Our system uses an active vision illumination technique and different image-processing pipelines for motion detection, both previously reported, providing a fully automated image processing pipeline. In addition, this study validated both these methods and the feasibility of the SiViS machine for lifespan experiments by comparing them with manual lifespan assays. Results demonstrated that the automated system yields consistent replicates (p-value log rank test 0.699), and there are no significant differences between automated system assays and traditionally manual assays (p-value 0.637). Finally, although we have focused on the use of SiViS in longevity assays, the system configuration is flexible and can, thus, be adapted to other C. elegans studies such as toxicity, mobility and behaviour.